Nanocrystals having small dimensions can have properties intermediate between molecular and bulk forms of matter and can exhibit quantum confinement of excitons in all three dimensions. Quantum confinement leads to an increase in the effective band gap of the material with decreasing crystallite size. In most applications of nanocrystals, it is desirable to have monodisperse nanocrystals, that is, nanocrystals of nearly all the same size.